UK Car Repair: 77 MGB wiring harness, engine loom, mgb tourer

Question
QUESTION: 1977 mgb tourer--1800cc---oct 1977
Hi,
I need to know the engine harness,to the dash harness connecting plug location,to replace engine harness and a brief answer on how to reach it and unplug.  I know the dash harness goes through hole behind wiper motor and through fire wall from engine behind washer bottle but I can't see a connection on either...I'm stuck!

ANSWER: Here's the layout.

http://www.moss-europe.co.uk/Graphics/UK/Products/schematics/DS017N-C.gif

The engine loom isn't detachable, consider it the main part of the loom - but I think the internal/dash loom can be disconnected from it, leaving a few connectors and the beginnings of the engine loom inside the car.



---------- FOLLOW-UP ----------

QUESTION: Christian,
can I splice into the engine wiring harness up by the firewall then, to replace the engine wiring harness.  From your answer to my first question, I think you are saying that the main harness goes from the engine compartment all the way to the trunk as one piece without connectors? The only part of the harness to be replaced is from the firewall down to the headlights, horns, etc.

thank you so much, Kay

Answer
Just keep cutting back the bad wires till you find shiny copper, that's your only objective. work on one wire at a time so it's impossible to make a mistake - So long as you solder everything nice and tight and use plenty good quality tape you shouldn't have any issues - I have spliced a 60 wire loom before now. :)

Best to remove all the tape from the part of the loom you are working on, cut and replace wires then re-tape the whole lot tight and tidy.

Remember to stagger your cuts so the joins aren't all in the same place, it's safer and less bulky like that.

I would go about it working from the furthest connector (prob LHS headlight), removing the tape as I go - until you get to healthy wire.
Replace each wire one at a time with the correct or better thickness replacement. Test everything works before soldering anything - just a bit of tape round any bare wires then test the light/indicator etc - once you're sure its 100% Solder and tape (self amalgamating tape is superior to anything else for around the joins) the loom back into a "loom" when finished.